• The anatomy and etiology of torticollis were studied in 37 cases. Proper roentgen examination is essential; necessary views are lateral stereograms of the cervical vertebrae, with anteroposterior openmouth views to identify the odontoid process and to show the symphysis of the mandible and the whole of the first four vertebrae.
The two most common findings are a unilateral subluxation between vertebrae C-2 and C-3 and a rotary subluxation between the atlas and the epistropheus. The two lesions sometimes coexist. Reduction is generally easy and in one instance was spontaneous. Diagnostic roentgen examination should be carried out before treatment such as traction or manipulation is instituted. The anatomic location and age distribution of these subluxations are partly explained by the obliquity of the articular surfaces, but other factors remain to be discovered.